On Tue, May 23, 2023 at 7:18 AM Chris Chilvers <chilversc@xxxxxxxxx> wrote: > > On Fri, 19 May 2023 at 10:40, David Howells <dhowells@xxxxxxxxxx> wrote: > > > > Chris Chilvers <chilversc@xxxxxxxxx> wrote: > > > > > While testing the fscache performance fixes [1] that were merged into 6.4-rc1 > > > it appears that the caching no longer works. The client will write to the cache > > > but never reads. > > > > Can you try reading from afs? You would need to enable CONFIG_AFS_FS in your > > kernel if it's not already set. > > > > Install kafs-client and do: > > > > systemctl enable afs.mount > > md5sum /afs/openafs.org/software/openafs/1.9.1/openafs-1.9.1-doc.tar.bz2 > > cat /proc/fs/fscache/stats > > FS-Cache statistics > Cookies: n=13 v=7 vcol=0 voom=0 > Acquire: n=13 ok=13 oom=0 > LRU : n=1 exp=0 rmv=0 drp=0 at=2833 > Invals : n=0 > Updates: n=0 rsz=0 rsn=0 > Relinqs: n=0 rtr=0 drop=0 > NoSpace: nwr=0 ncr=0 cull=0 > IO : rd=0 wr=18 > RdHelp : RA=18 RP=0 WB=0 WBZ=0 rr=0 sr=0 > RdHelp : ZR=1 sh=0 sk=0 > RdHelp : DL=18 ds=18 df=0 di=0 > RdHelp : RD=0 rs=0 rf=0 > RdHelp : WR=18 ws=18 wf=0 > > This was on an instance that was only just created, so the cache was > initially unused (all the counters were 0). > > > umount /afs/openafs.org > > md5sum /afs/openafs.org/software/openafs/1.9.1/openafs-1.9.1-doc.tar.bz2 > > cat /proc/fs/fscache/stats > > FS-Cache statistics > Cookies: n=13 v=7 vcol=0 voom=0 > Acquire: n=26 ok=26 oom=0 > LRU : n=1 exp=1 rmv=0 drp=0 at=467 > Invals : n=0 > Updates: n=0 rsz=0 rsn=0 > Relinqs: n=13 rtr=0 drop=13 > NoSpace: nwr=0 ncr=0 cull=0 > IO : rd=18 wr=18 > RdHelp : RA=36 RP=0 WB=0 WBZ=0 rr=0 sr=0 > RdHelp : ZR=1 sh=0 sk=0 > RdHelp : DL=18 ds=18 df=0 di=0 > RdHelp : RD=18 rs=18 rf=0 > RdHelp : WR=18 ws=18 wf=0 > > Looks like the cache is working fine with AFS. The second md5sum > seemed a lot quicker than the first. > > -- > Linux-cachefs mailing list > Linux-cachefs@xxxxxxxxxx > https://listman.redhat.com/mailman/listinfo/linux-cachefs > I don't think this test demonstrates the failure Chris is seeing, or correct me if I'm wrong Chris. Chris, does this same test fail for you with NFS on 6.4-rc1? The same test passes for me with NFSv3. 1st time through: writes to the cache seen, no reads: IO : rd=0 wr=16 2nd time through: reads from the cache seen, no writes: IO : rd=16 wr=16 # mount -o vers=3,fsc 127.0.0.1:/export/ /mnt/nfs # cat /proc/fs/fscache/stats FS-Cache statistics Cookies: n=0 v=1 vcol=0 voom=0 Acquire: n=0 ok=0 oom=0 LRU : n=0 exp=0 rmv=0 drp=0 at=0 Invals : n=0 Updates: n=0 rsz=0 rsn=0 Relinqs: n=0 rtr=0 drop=0 NoSpace: nwr=0 ncr=0 cull=0 IO : rd=0 wr=0 RdHelp : RA=0 RP=0 WB=0 WBZ=0 rr=0 sr=0 RdHelp : ZR=0 sh=0 sk=0 RdHelp : DL=0 ds=0 df=0 di=0 RdHelp : RD=0 rs=0 rf=0 RdHelp : WR=0 ws=0 wf=0 # md5sum /mnt/nfs/openafs-1.9.1-doc.tar.bz2 ca25530ec01afc3b71bc081bc93b87cf /mnt/nfs/openafs-1.9.1-doc.tar.bz2 # cat /proc/fs/fscache/stats FS-Cache statistics Cookies: n=1 v=1 vcol=0 voom=0 Acquire: n=1 ok=1 oom=0 LRU : n=1 exp=0 rmv=0 drp=0 at=6444 Invals : n=0 Updates: n=1 rsz=0 rsn=0 Relinqs: n=0 rtr=0 drop=0 NoSpace: nwr=0 ncr=0 cull=0 IO : rd=0 wr=16 RdHelp : RA=16 RP=0 WB=0 WBZ=0 rr=0 sr=0 RdHelp : ZR=1 sh=0 sk=0 RdHelp : DL=16 ds=16 df=0 di=0 RdHelp : RD=0 rs=0 rf=0 RdHelp : WR=16 ws=16 wf=0 # umount /mnt/nfs # mount -o vers=3,fsc 127.0.0.1:/export/ /mnt/nfs # md5sum /mnt/nfs/openafs-1.9.1-doc.tar.bz2 ca25530ec01afc3b71bc081bc93b87cf /mnt/nfs/openafs-1.9.1-doc.tar.bz2 # cat /proc/fs/fscache/stats FS-Cache statistics Cookies: n=1 v=1 vcol=0 voom=0 Acquire: n=2 ok=2 oom=0 LRU : n=1 exp=1 rmv=0 drp=0 at=6710 Invals : n=0 Updates: n=2 rsz=0 rsn=0 Relinqs: n=1 rtr=0 drop=1 NoSpace: nwr=0 ncr=0 cull=0 IO : rd=16 wr=16 RdHelp : RA=32 RP=0 WB=0 WBZ=0 rr=0 sr=0 RdHelp : ZR=1 sh=0 sk=0 RdHelp : DL=16 ds=16 df=0 di=0 RdHelp : RD=16 rs=16 rf=0 RdHelp : WR=16 ws=16 wf=0 # uname -r 6.4.0-rc1 -- Linux-cachefs mailing list Linux-cachefs@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/linux-cachefs
